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I'm just getting around 29 or 30 mpg over the past two years in my 2010 335d, and see reports of 34-36 from other posters. Arrgh!

Is it an issue of tire pressures? We don't do "jack rabbit" starts, though I should tell you that most of our trips are short in-town jaunts. There are no bricks or whacked hoodlums in the trunk. The passenger load is usually one or two.

On freeways, we average about 70-75 (don't tell anyone). We use Shell diesel.

Any thoughts as to how we can improve our performance (uh...that would be mileage)?

My MPG has been steady in the 29-31MPG range since new. I have a regular commute about 36 miles one way and it is approx 60/40 highway/city. City kills your MPG in these cars. And if you drive like you stole it on the Hwy, you get right about 30MPG.

On road trips I saw 36mpg doing 70-80mph.

The A/C will also have about a 1.5-2.0mpg affect between summer and winter here in Florida.

I think you are doing really good if most of your driving is short in town trips. My car has averaged around 29mpg since new. Most of my driving is on the freeway but traffic happens a lot. It is the stop n go behavior that kills mpg in these. At least that has been my experience.

...though I should tell you that most of our trips are short in-town jaunts.

After a combined 4 years with my two diesels I've concluded that diesels are not well suited for city driving....including in terms of fuel economy.My experience is that they both were/are *very* well suited for the Interstate at a steady 70mph which,thankfully,discribes 90% of my miles.If you ever get a chance to cruise a traffic free Interstate at 70mph for a few hundred miles (which I've done a number of times) your mileage figures will bring a smile to your face!

One thing I have noticed (at least from the OBC and the mpg gauge, if you can believe them) the 335d does its best at maintaining a certain speed with optimal mileage. Accelerating, is not its strong suit, at least in terms of fuel consumption (I am having a verrrry hard time avoiding accelerating ALL the time in this beast). On a flat road I can keep the mpg gauge pasted a 50+mpg at 75mph, of course with the hills it decreases. Just starting from a light with 1/4 throttle will peg it in the opposite direction.

Not even getting into hyper-milling or whatever it is called, simply accelerating reasonably to a speed and maintaining that speed is what I have found does the best - again assuming you can trust the electronics. Now my car is brand new to me (2 weeks) so I am having a bit too much fun at the moment so I tend to be around 26 mpg (70% city). However, I did try a few tests and paying attention to and minimizing long medium to high periods of acceleration and deceleration improved my fuel efficiency by about 4-6 mpg. Of course you can take it to extremes if you want, but in standard mixed cty/hwy driving smooth acceleration to speed and maintaining that speed (within reason of course - traffic kills it) is what I found works best.

...
I believe that the new diesel for the 3 series will be downgraded, though BMW says that its performance will be the same...I'm not so sure...

How about the hybrid (3AH or whatever) vs. the new 3 series diesel (when it arrives) in terms of mpg?

But, as has been said, "The torque didn't bring ya."

It may well be that the 335d engine may go into the 535d, which is a bigger and heavier car. And it may go into the X3d when it appears.
...

Not sure where the claim for same performance as the 335d came from. The first 3er diesel will be a 2L single turbo (180hp/280 lb-ft), vs the 3L dual turbo in the 335d.

The 320d (equivalent to the '328d' coming here) combined fuel economy is over 30% better than the Active3 hybrid, but that is really not a fair comparison. Two totally different vehicles. The hybrid has power close to 335i and much better fuel economy.

The engine in your 335d won't be coming over here in the 5. That engine power output is the same as the single turbo 3L found in the 530d.

One thing I have noticed (at least from the OBC and the mpg gauge, if you can believe them) the 335d does its best at maintaining a certain speed with optimal mileage. Accelerating, is not its strong suit, at least in terms of fuel consumption (I am having a verrrry hard time avoiding accelerating ALL the time in this beast). On a flat road I can keep the mpg gauge pasted a 50+mpg at 75mph, of course with the hills it decreases. Just starting from a light with 1/4 throttle will peg it in the opposite direction.

Not even getting into hyper-milling or whatever it is called, simply accelerating reasonably to a speed and maintaining that speed is what I have found does the best - again assuming you can trust the electronics. Now my car is brand new to me (2 weeks) so I am having a bit too much fun at the moment so I tend to be around 26 mpg (70% city). However, I did try a few tests and paying attention to and minimizing long medium to high periods of acceleration and deceleration improved my fuel efficiency by about 4-6 mpg. Of course you can take it to extremes if you want, but in standard mixed cty/hwy driving smooth acceleration to speed and maintaining that speed (within reason of course - traffic kills it) is what I found works best.

I really think this is because of the smaller turbo and how easily it builds boost. But then that smaller turbo to me is what adds to a lot of the daily driving enjoyment.

Not even getting into hyper-milling or whatever it is called, simply accelerating reasonably to a speed and maintaining that speed is what I have found does the best - again assuming you can trust the electronics.

This is what I have noticed as well after a year of driving the car. Seems to get best highway mileage if you accelerate briskly to speed, then just maintan speed. If you go up a hill, again put some power into it then just maintain once you achieve the needed speed. I can get better MPG NOT using cruse control on anything but a perfectly level road. Accelerating slowly actually yields relatively poor mileage.

This is what I have noticed as well after a year of driving the car. Seems to get best highway mileage if you accelerate briskly to speed, then just maintan speed. If you go up a hill, again put some power into it then just maintain once you achieve the needed speed. I can get better MPG NOT using cruse control on anything but a perfectly level road. Accelerating slowly actually yields relatively poor mileage.

Agreed on this last point; however, flooring it to get there is probably even worse :-)

I don't think I have seen my best tankful yet. Best I got was on an interstate jaunt for about 3/4 of the tank, the balance was suburbia. For that I got 37.1mpg over the whole tank. I bet if I was on an all-day trip across the USA heartland it might get a calculated 40mpg. You can see what my current average is around suburban Maryland near Annapolis over my 25 fillups. I do not baby it except until it warms up. Unless it is just to the nearby grocery store only, I make it a practice to goose it at least a couple of times on every trip.

I make it a practice to goose it at least a couple of times on every trip.

I call this an Italian tune up. My driving is mainly surface streets on my 4.5 mile commute. So, I feel like i need to drive her (named Deedee) like she was meant to. I'm scared the DPF will screw up if I don't romp on it every once in a while. I have a real flat drive to Galveston occasionally. I reset the mileage computer and set cruise to ~68. I routinely see 40 to 42 mpg when cool enough to not run A/C. There are times that i reset and see mileage at 33 mpg and i'm guessing that is when a regen is happening. I don't have the fancy gismos that TDIwise has to see a regen is happening.